Will my flight be on time?

Shortly after this post is published, I will be heading to O’Hare to fly to a conference in New York. Will my flight be on time?

That is actually a slightly ambiguous question. The airlines have some leeway in how they schedule flights. It is not ordained by God that Flight 398 should take two hours and five minutes. That was American Airlines’ decision. The schedulers at AA could as easily have deemed that the flight would take two hours on the money or two hours ten minutes and no one would have really questioned the change.

American, Alaska, United and Southwest airlines have all reduced scheduled time for trips in at least 16 of the past 24 months, according to the Official Airline Guide data compiled by American. Together, the nine biggest airlines took an average of one minute per flight out of their schedules last year, according to American’s schedule analysis. That may not sound like a lot, but minutes add up to days across thousands of flights. At just American, a one-minute change in schedules represents a total of 24.2 flight hours across its fleet each day.

Here the author of the piece discusses some of his findings.

Vodpod videos no longer available.

There are a couple interesting things here. One is the rationale for why airlines have tried to reduce their flight times. A partial explanation is that past attempts to pad schedules have backfired as airlines have had trouble synchronizing the departure and arrival of successive flights.

Airlines began aggressively padding schedules in 2008 and 2009 so that even late flights technically arrive on time. This can be frustrating to travelers: Fluctuating fight times mean planes often arrive well before gates are available, so passengers are left waiting on board.

Another point is that different firms have taken on the challenge shortening the allotted time for flights in different ways. American, for example, has tried to deal directly with the synchronization issue.

American says it trimmed a minute or two off flight schedules in Dallas-Fort Worth, its largest hub, simply by making sure it had enough gates for arriving flights—something that had been a chronic problem.

“Even if you arrive on time, the goodwill is blown, and people think we are idiots,” said Jonathan Snook, American’s vice president of operations planning and performance.

American also sliced minutes off flights headed to spoke cities, then added minutes to flights headed into hubs. That way fewer planes sit at the gate waiting for connecting passengers.

Delta, on the other hand, has adjusted times across the week to reflecting that the utilization of its resources (and hence the impact of congestion) varies across the week.

Delta Air Lines, for example, had the same flight schedules Monday through Friday. Now, it has shaved time off flights on Tuesdays, Wednesdays and Saturdays—days when there are fewer planes in the sky and thus fewer delays.

On Mondays, Delta operates 160 more flights than it does on Tuesdays. So on Mondays, Flight 812 from Atlanta to Chicago is scheduled for 2 hours, 10 minutes. On Tuesdays, Flight 812 is scheduled for 2 hours, 3 minutes.

US Air seems to have aimed for actual operational improvements.

US Airways Group Inc. has reduced its “block times”—the time it takes to get from gate to gate—with a major push to have planes depart precisely at the scheduled time, or earlier. Once a plane leaves late for one flight, it often runs late for the rest of its flights that day. And delays can grow exponentially—a flight off the gate late may find a long line of planes waiting to take off, or may find that its gate is no longer available at its destination. So it waits even longer.

“You can do all sorts of things to make up for poor performance,” said Robert Isom, chief operating officer at US Airways, referring to padded schedules. “But you sacrifice efficiency, the passenger experience, the employee experience and profits.”

This last one is particularly interesting since it highlights the interrelated nature of flights. That is, the question isn’t just whether my flight will be on time but whether it will make yours late.